Frozen Grotto

Note that the above rewards are for slaying the Terato Dragon, who only spawns once every 5 days.

To enter Frozen Grotto, find the NPC in Desert City.

Once inside, You’ll need to obtain the Fire Emblem from the first floor in order to move onto the second. All enemies have around the same rate to drop Fire Emblems.

Note that the rates are pretty low since the Terato Dragon only spawns once every 5 days, if you get an emblem, just hang onto it until the dragon boss has spawned. (unless you just want to level on harder enemies.)

Once you have a Fire Emblem you can go to the blue dot on the map and be sent to the second floor.

On the second floor there are four Boss enemies that have a high change to drop an Ice Emblem to get to the third floor.

Find the Frozen Grotto envoy with the Ice Emblem to get sent to the final floor.

Last Floor! Lair of the Terato Dragon!… Assuming he happens to be home.

Alright So I can’t really make a good guide here because there is no mini map on this floor. All I can tell you is that you have to go right, then up, then left, then down. The map is a counter-clockwise spiral with the dragoin being almost directly up from where you first enter the map.

Heres a screenshot of where the Terato Dragon spawns:

And another screenshot of the Terato Dragon biting me in the face:

If you slay the Terato Dragon then congratulations! You beat the hardest Boss in Serenity CO.

He has a VERY high chance of dropping a Super Socketed non-weapon equipment and usually explodes out Dragonballs.

Again the Terato Dragon is one of the Bosses that cycle off, spawning a different Boss every day in a 5 day loop.